module Slot: sig .. endtype t = Printexc.backtrace_slot;
let is_raise: t => bool;
is_raise slot is true when slot refers to a raising
point in the code, and false when it comes from a simple
function call.let location: t => option(Printexc.location);
location slot returns the location information of the slot,
if available, and None otherwise.
Some possible reasons for failing to return a location are as follow:
-g)let format: (int, t) => option(string);
format pos slot returns the string representation of slot as
raw_backtrace_to_string would format it, assuming it is the
pos-th element of the backtrace: the 0-th element is
pretty-printed differently than the others.
Whole-backtrace printing functions also skip some uninformative
slots; in that case, format pos slot returns None.
Since 4.02